1. Field of the Invention
The present invention relates to an intake mouth for a whirlpool-type or similar type of bathtub. The present invention is adapted to prevent accidents from occurring such as may be brought about by hair remaining trapped in the intake and the consequences resulting therefrom under the circumstances, which may involve such serious consequences as drowning.
2. Description of the Prior Art
It is generally known that a water recirculation flow is generated in whirlpool-type bathtubs. A pump takes water from the interior of the tub through an intake mouth and sends the water to a plurality of jet nozzles which, after mixing the water with air, again eject the water under pressure into the interior of the tub.
In order to minimize the likelihood of the above-referenced accidents from occurring due to hair or other materials remaining trapped at the front of a grill at the intake mouth, a number of solutions have been proposed. These involve, for example, the use of floats and/or electric or magnetic switches for detecting and reacting to possible clogging conditions of the intake mouth and cutting off the operation of the recirculating pump. These types of solutions, however, are undesirably complicated, expensive and not very reliable, considering the criticality of the operation of the component parts used in connection therewith.
A simpler and lower-cost solution is described WO 96/18335. This solution provides for a part of the water flow taken in through the intake mouth to pass through a central tube which has a reduced cross-sectional area in order to normally balance the weight of the water column present in a vent pipe connected to the intake side of the recirculating pump. When the intake mouth becomes frontally clogged by trapped hair or the like, in positional correspondence with the central tube, the vent pipe becomes empty, discharging the water contained therein. It then starts conveying air toward the suction or intake side of the pump, and as a result the pump becomes unprimed, i.e. deactivates. This then allows for the foreign matter that led to the clogging to be conveniently removed.
This solution allows for the pump to be controlled in a simple manner. However, the solution also implies rather serious drawbacks. In fact, the solution of WO 96/18335 is only capable of detecting or identifying foreign matter that remains trapped in correspondence of a reduced frontal surface area of the intake valve, i.e. the surface area that practically corresponds to the cross-sectional area of the central tube. On the other hand, if the contrary case occurs, that is, if the foreign matter remains trapped along the remaining portions of the front surface of the intake mouth, this condition substantially fails to be identified or detected. Accordingly, the intake mouth is only effective under certain conditions, and on the whole turns out to be undesirably unsafe.